Human hair becomes soiled due to its contact with the surrounding atmosphere and, to a greater extent, from sebum secreted by the head. The build-up of the sebum causes the hair to have a dirty feel and an unattractive appearance. The soiling of the hair necessitates it being shampooed with frequent regularity.
Shampooing the hair cleans by removing excess soil and sebum. However, the shampooing process has disadvantages in that the hair is left in a wet, tangled and generally unmanageable state. Shampooing can also result in the hair becoming dry or "frizzy" due to removal of natural of natural oils or other hair moisturizing materials. After shampooing, the hair can also suffer from a loss of "softness" perceived by the user upon drying. A variety of approaches have been developed to alleviate the after-shampoo problems. These range from the inclusion of hair conditioning aids in shampoos to post-shampoo application of hair conditioners, i.e., hair rinses. Hair rinses are generaly liquid in nature and must be applied in a separate step following the shampooing, left on the hair for a length of time, and rinsed with fresh water. This, of course, is time consuming and is not convenient.
While a wide variety of shampoos have been disclosed which contain conditioning aids, they have not been totally satisfactory for a variety of reasons. One problem relates to compatibility problems between good cleaning anionic surfactants and the many conventional cationic agents which historically have been used as conditioning agents, including both carbonic surfactants and cationic polymers.
Whereas efforts have been made to minimize adverse interaction through the use of alternate surfactants and improved cationic conditioning agents, it remains highly desirable to utilize anionic surfactants in shampoo compositions. Furthermore, cationic conditioning agents commonly do not provide optimal overall conditioning benefits, particularly in the area of "softness", especially when delivered as an ingredient in a shampoo composition. Many cationic polymers, additionally, tend to build up on the hair to result in an undesirable, "unclean" coated feel.
Materials which can provide increased softness are nonionic silicones. Silicones in shampoo compositions have been disclosed in a number of different publications. Such publications include U.S. Pat. No. 2,826,551, Geen, issued Mar. 11, 1958; U.S. Pat. No. 3,964,500, Drakoff, issued Jun. 22, 1976; U.S. Pat. No. 4,364,837, Pader, issued Dec. 21, 1982; and British Patent 849,433, Woolston, issued Sep. 28, 1960. While these patents disclose silicone containing compositions, they also did not provide a totally satisfactory product in that it was difficult to maintain the silicone well dispersed and suspended in the product. Recently, stable, insoluble silicone-containing hair conditioning shampoo compositions have been described in U.S. Pat. No. 4,741,855, Grote and Russell, issued May 3, 1988 and U.S. Pat. No. 4,788,006, Bolich and Williams, issued Nov. 29, 1988. These shampoo compositions can deliver excellent overall conditioning benefits to the hair while maintaining excellent cleaning performance, even with the use of anionic detersive surfactants, for a wide variety of hair types. However, it would be desirable to improve these types of shampoos such that they provided improved conditioning benefits to one type of hair in particular, that type being hair damaged by permanent treatments (i.e., "perms"), color treatments, and bleach treatments, applied either at hair salons or at home. Unfortunately, silicone hair conditioner efficacy for permed hair appears to be lower than that for most undamaged hair. It would be desirable to provide a shampoo composition that would provide excellent overall cleaning and conditioning benefits for such hair, as well as other types of hair not subjected to such treatments. This would reduce the need for families or other residents to purchase separate hair conditioning shampoo products for persons with damaged and undamaged hair.
It is an object of this invention to provide shampoo compositions, which can provide excellent cleaning performance and excellent overall hair conditioning for such damaged hair as well as for hair not subjected to such treatments ("undamaged hair").
It is a further object of this invention to provide an improved anionic surfactant-containing shampoo compositions that can provide excellent cleaning performance and conditioning performance for both damaged and undamaged hair types, such that the shampooed hair can have desirable levels of manageability, combability, softness, and low or reduced levels of dryness.
These objects will become apparent from the description which follows, as many other objects become apparent upon a reading of said description.
Unless otherwise indicated, all percentages are calculated by weight of the total composition, and all ratios are calculated on a weight basis.